Japanese Patent Laid-open No. 8-262573 discloses the structure in which outside air supplied from an in-flow hole above a lamp house is guided in the direction of a light emitting portion of a light source along an air induction member, directly cools a heat generation portion and flows outside a lamp chamber from a lower out-flow hole.
Further, Japanese Patent Laid-open No. 2002-189247 discloses the structure in which a blower hole for sending cooling air toward the interior of a reflector is formed, and the air direction changing means for changing the direction of cooling air discharged toward the interior of the reflector is provided.
Furthermore, Japanese Patent Laid-open No. 10-27518 discloses the technique in which an air-flow is introduced into a reflector from a duct to cool a lamp.